Methods For Producing Fluids From Geological Formation

Abstract

Embodiments disclosed herein relate to reservoir characterization techniques and methods for accurately predicting scale tendencies of formation fluids, developed with the newly discovered phenomena that extreme downhole conditions affect the properties of reservoir fluids, including both the brine and dense hydrocarbon gas phases. In one aspect, there is disclosed a method for producing fluids from a geological formation. The method comprises inputting at least one property of a geological formation into an equation of state (EOS) model. The EOS model accounts for bound water, a high temperature effect on the brine and a high temperature effect on the dense gas phase. The EOS model is solved to determine a character of fluids contained in the geological formation, and inputting a production condition or a plurality of production conditions into the EOS model. A character of the fluids is determined based on the determined character of the fluids in the geological formation and the input production conditions. The solution can be output to a display device. Planning of the production of fluids from the geological formation can be performed. Production conditions can be controlled or adjusted.

What is claimed: 
     
         1 . A method for producing fluids from a geological formation, the method comprising:
 (a) inputting at least one first property of a geological formation into an equation of state (EOS) model, the EOS model accounting for bound water, a high temperature effect on the brine and a high temperature effect on the dense gas phase;   (b) solving the EOS model to determine a character of fluids contained in the geological formation;   (c) inputting one or more production conditions into the EOS model;   (d) solving the EOS model to determine a character of the fluids based on the determined character of the fluids in the geological formation and the input production conditions;   (e) at least one of:
 (i) outputting the solution in (b), (d), a combination thereof, or data derived therefrom to a display device; 
 (ii) planning production of fluids from the geological formation based on the solutions in (b), (d), or combinations thereof; 
 (iii) controlling or adjusting production conditions based on the solutions in (b), (d), or combinations thereof. 
   
     
     
         2 . The method of  claim 1 , further comprising:
 measuring the at least one property of the geological formation using a downhole measurement device.   
     
     
         3 . The method of  claim 1 , further comprising repeating (c) and (d) to map a character of the fluids along a production flow channel. 
     
     
         4 . The method of  claim 1 , further comprising repeating (c) and (d) to map a character of the fluids proximate a location along a production flow channel. 
     
     
         5 . The method of  claim 1 , further comprising repeating (c) and (d) to map a change in the character of the fluids over a time period of production. 
     
     
         6 . The method of  claim 1 , wherein the inputting one or more production conditions comprises inputting at least one of a flow rate, a temperature, a concentration, and a type of control agent, the solving further comprising:
 determining an effect of the control agent on the character of the fluids at the input production conditions.   
     
     
         7 . The method of  claim 6 , further comprising screening control agents to estimate their potential effectiveness for inhibiting scale formation along a production flow channel or proximate a location in the production flow channel. 
     
     
         8 . The method of  claim 6 , further comprising determining a minimum effective amount of a control agent for inhibiting scale formation along a production flow channel or proximate a location in the production flow channel. 
     
     
         9 . The method of  claim 6 , further comprising adjusting or controlling a flow rate of a control agent to a production flow channel or location in a production flow channel based on the determined effect of the control agent on the character of the fluids. 
     
     
         10 . The method of  claim 1 , wherein the solving the EOS model to determine a character of the fluids based on the determined character of the fluids in the geological formation and the input production conditions further comprises determining a time to transition from an initial production condition to a final production condition. 
     
     
         11 . The method of  claim 10 , further comprising analyzing the determined transition time to determine if the change from the initial production condition to the final production condition is operationally significant. 
     
     
         12 . A method for screening control agents used during production of fluids from a geological formation, the method comprising:
 (a) inputting at least one first property of a geological formation into an equation of state (EOS) model, the EOS model accounting for bound water, a high temperature effect on the brine and a high temperature effect on the dense gas phase;   (b) solving the EOS model to determine a character of fluids contained in the geological formation;   (c) inputting one or more production conditions into the EOS model, including at least one of a flow rate, a temperature, a concentration, and a type of control agent;   (d) solving the EOS model to determine a character of the fluids based on the determined character of the fluids in the geological formation and the input production conditions to determine an effect of the control agent on the character of the fluids at the input production conditions;   (e) at least one of:
 (i) outputting the solution in (b), (d), a combination thereof, or data derived therefrom to a display device; 
 (ii) planning production of fluids from the geological formation based on the solutions in (b), (d), or combinations thereof; 
 (iii) controlling or adjusting production conditions based on the solutions in (b), (d), or combinations thereof. 
   
     
     
         13 . The method of  claim 12 , further comprising screening control agents to estimate their potential effectiveness for inhibiting scale formation along a production flow channel or proximate a location in the production flow channel based on the determined effect. 
     
     
         14 . The method of  claim 12 , further comprising determining a minimum effective amount of a control agent for inhibiting scale formation along a production flow channel or proximate a location in the production flow channel based on the determined effect. 
     
     
         15 . The method of  claim 12 , further comprising adjusting or controlling a flow rate of a control agent to a production flow channel or location in a production flow channel based on the determined effect of the control agent on the character of the fluids based on the determined effect. 
     
     
         16 . A method for producing fluids from a geological formation, the method comprising:
 (a) inputting at least one first property of a geological formation into an equation of state (EOS) model, the EOS model accounting for bound water, a high temperature effect on the brine and a high temperature effect on the dense gas phase;   (b) solving the EOS model to determine a character of fluids contained in the geological formation;   (c) inputting one or more production conditions into the EOS model;   (d) solving the EOS model to determine scale tendencies of the fluids based on the determined character of the fluids in the geological formation and the input production conditions;   (e) at least one of:
 (i) outputting the solution in (d) or data derived therefrom to a display device; 
 (ii) planning production of fluids based on the determined scale tendencies; and 
 (iii) controlling or adjusting production conditions based on determined scale tendencies. 
   
     
     
         17 . The method of  claim 16 , further comprising:
 measuring the at least one property of the geological formation using a downhole measurement device.   
     
     
         18 . The method of  claim 16 , further comprising repeating steps (c) and (d) to map scale tendencies of the fluids along a production flow channel. 
     
     
         19 . The method of  claim 16 , further comprising repeating steps (c) and (d) to map scale tendencies of the fluids proximate a location along a production flow channel. 
     
     
         20 . The method of  claim 16 , further comprising repeating steps (c) and (d) to map a change in the scale tendencies of the fluids over a time period of production.